USS Mercy explained

Three hospital ships of the United States Navy have borne the nameUSS Mercy, in honor of the virtue of compassion (and owing to their purpose).

• , was built in 1907 as Saratoga and was commissioned Mercy (ID-1305) on 24 January 1918, before being re-designated AH-4 in 1920. She served in the Atlantic Fleet during World War I.
• , was a commissioned on 7 August 1944. She served during World War II.
• , was placed in service in 1986 and served during the Gulf War, as well as numerous Humanitarian Assistance Missions. She is currently in active service.